Meanwhile, a federal grand jury in Seattle indicted the Mastros Thursday on 43 counts of bankruptcy fraud and money laundering — 37 more counts than they had been charged with previously in a criminal complaint issued in August 2011 that was the basis for their arrests.

Frush said the Mastros had been living in the Lake Annecy area for about a year. Le Dauphiné Libéré, a French newspaper, reported the Mastros had been renting a house under their own names in Doussard, on Lake Annecy.

The Mastros disappeared in June 2011 after failing to comply with a bankruptcy judge’s order that they turn over two giant diamond rings valued at $1.4 million. The judge later ruled the rings belonged to Michael Mastro’s creditors.

Mastro, 87, a longtime Seattle real-estate developer and lender, was pushed into one of Washington’s largest bankruptcies ever in 2009 after the recession undermined his real-estate empire.

His debts to unsecured creditors have been estimated at $250 million.

The new grand-jury indictment — product of a federal investigation that began nearly three years ago — charges that Mastro, anticipating bankruptcy, engaged in a series of illegal transactions aimed at putting several valuable assets off-limits to creditors.

Those assets included the rings and the Mastros’ Medina waterfront mansion, purchased for $15 million in 2006. A bankruptcy judge has since ruled the house, like the rings, rightfully belongs to creditors, and it has been sold.

The rings’ whereabouts still are unknown.

The Mastros also failed to disclose to court officials a bank account they used to make more than $761,000 in personal purchases after Mastro entered bankruptcy, the indictment says.

Those purchases included $107,000 in gold coins.

The indictment also alleges the Mastros made false statements about the assets under oath or penalty of perjury on numerous occasions.

Most of the information in the charges was developed by James Rigby, the court-appointed trustee charged with finding and liquidating Mastro’s assets and distributing them to creditors.

Frush said he doubts prosecutors can prove the Mastros engaged in an intentional scheme to defraud.

“The allegations against the Mastros are serious, and the FBI is committed to ensuring that they face those charges,” Steven Dean, assistant special agent in charge in the FBI’s Seattle office, said in a prepared statement.

Before the Mastros can be tried, however, they must be returned from France. And that may not be easy, or quick.

Bankruptcy fraud appears to be an offense subject to extradition under the treaty between the U.S. and France, said Douglas McNabb, an extradition attorney in Washington, D.C.

But if the Mastros exercise all their appeals, it could take a year or two before they are sent home, he added.

The treaty says people can be extradited if they are charged with crimes punishable by at least a year in prison in both countries. Bankruptcy fraud carries such a sentence in the U.S., McNabb said, but he’s not certain if it does in France.

When word of the Mastros’ arrest broke Wednesday, Joe and Gayle Colello, of Seattle, opened a good bottle of white wine that night and toasted the news.

They were among about 200 individual “Friends & Family” investors in Mastro’s ventures, loaning the real-estate magnate a total of about $100 million in return for pledges of above-market interest payments.

Most of that investment has disappeared. Investors have gotten back about a penny on the dollar so far, and Rigby has said they probably won’t get much more.

“I’m glad they got him,” Joe Colello said of Mastro Thursday.

“He’s really caused tremendous hardship to a lot of families. He’s a man without a conscience.”